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Tuesday, June 30, 2009

There are small regions scattered across the east coast of the United States where, at the right time of year, in the right patch of habitat, you may have a chance to find perhaps the most beautiful amphibian in North America, the Pine Barrens tree frog, Hyla andersonii. Pine Barrens Tree Frogs are a small (less than 2 inches long), bright green frog with a lavender bordered light-brown patch running through its eye and alongside its chest. At the rear end of its body, the brown patch is blotted with bright yellow spots. It’s a striking amphibian that many photographers long to capture.These tree frogs have an intriguing and unique distribution; only residing within the Pine Barrens of New Jersey (hence their name), the Carolinas, and the western Florida panhandle and adjacent areas of Alabama. Many herpetologists have spent considerable time pondering their patchy range. How groups of this little frog could be separated by thousands of miles begs an answer. Perhaps when the climate was more favorable to amphibians, Pine Barrens tree frog populations were connected by a vast expanse of wetlands. Before we drained, paved over, and developed so many bogs, swamps, and marshes across our country, perhaps there were more populations to fill in the gaps. Of considerable interest is how this frog has become slightly different within the remaining areas where they are found, without any gene exchange between populations, frogs in a particular area become suited to their local environment and over time, their behavior and morphology has begun to vary from other groups.In any case, today this isn’t a frog you’re likely to find by accident. Unlike your typical bullfrog or green tree frog, which can be found in just about any wet area within their range, Pine Barrens tree frogs have very specific habitat requirements. Within Alabama and Florida you may be able to see one in the wet and acidic seepages and bogs that surround some small streams, in the thickest brush and woody shrubs you’ve ever encountered. It’s no surprise that this species evaded detection in Florida and Alabama until relatively recently (although they haven’t yet been documented in adjacent Georgia, the search continues).The first individual Pine Barrens tree frog was documented in Florida in 1970 but we only began to better understand where they could be found in that state in the late 1970’s and early 1980s. Our knowledge of the frog’s status in Alabama developed slowly as well. Dr. Robert Mount, professor emeritus at Auburn University, recently came into the lab and related to me his surprise after being informed nearly 30 years ago that a Florida herpetologist had found the frog in Alabama. Mount, who wrote the book on Alabama amphibians and reptiles (literally), didn’t believe the news. For him to acknowledge that this creature was found in the state, he’d have to see it for himself, or, as it turned out, to hear it.Male Pine Barrens Tree Frogs, like many frog species, call to attract females. As each species has a unique and specific sound, you can identify the frogs in an area just by listening. But it’s not quite that easy. Different species call at different times of year, typically at night and especially following rains. So, there is certain amount of skill and timing required to determine if a frog is present. But there are some other amphibian quirks that you can exploit.Male frogs, although they desperately want all the nearby females to notice them, don’t want to be the only one singing in a pond. The frogs that tend to conduct solo performances are noticed not only by interested females, but are zeroed in on by hungry snakes and birds as well. As a result, most frogs prefer the relative anonymity of a full chorus of amorous amphibians before they’ll commence their crooning. But who’s going to be the first one to start singing? Dr. Mount, of course.By imitating the Pine Barrens Tree frog call, a nasal and rapid-fire, “Kwek Kwek Kwek Kwek”, you may stimulate nearby frogs to follow suit. After Dr. Mount was convinced that this frog did indeed exist in Alabama, he initiated an intensive survey across the southern portion of the state to determine their status and distribution. After identifying and arriving at potential wetlands, Dr. Mount would get out of his car, stand near the water’s edge, hold his hands to his mouth and offer forth his best, “Kwek Kwek Kwek Kwek Kwek”. After only a brief moment, there’s a good chance that any present male Pine Barrens Tree Frogs would answer. And there’s an even better chance he got some very strange looks from passing motorists. As a result of his efforts and another follow up study, the species was documented at about 35 sites in three Alabama counties, just a small corner of the state.When I learned I was to be conducting my dissertation field work in the Florida panhandle, the heart of the species distribution in the area, finding a Pine Barrens Tree Frog was at the top of my list of things to accomplish. When my Auburn officemate Sean Graham came down to visit, it was the excuse I’d been waiting for. Armed with a map of known locations, a group of us waited until dark and headed to some nearby creeks. As we drove along, we stopped at each creek crossing and piled out of the truck to try our luck. Tip-toeing silently to the edge of the creek bridge, Graham would let loose his best tree frog imitation and we’d all strain our ears to hear any response. After several performances with no appreciative amphibian response, Sean turned to us and exasperatedly exclaimed, “It’ll work better if there’s more people trying!”Rolling my eyes, I raised my hands to my mouth, held one nostril close with my finger and added my amateurish, “Kwek Kwek Kwek Kwek” to our concert. In the distance, seemingly far from the wetland, we finally heard our answer. We all turned to each other to excitedly whisper to each other, “Did you hear that?” The consistent answer was, “Of course!” But the single frog we heard at the first site seemed too distant and not near any wetland we could distinguish.Encouraged to know that our technique and our voices may prove irresistible to Pine Barrens Tree Frogs, we set out to another creek to find frogs that we might be able to see as well as hear. After arriving at the next creek and immediately after the night was filled with our enthusiastic amphibian impersonations, we heard several frogs echoing us from the wet areas alongside the stream, from within the deepest recess of seemingly impenetrable brush.“I’m going in.” Graham shouted as he jumped into the thicket. He was instantly enveloped by the vegetation and made invisible, but we could hear him crashing through the branches and cursing. Thinking myself wily, I decided to walk along the stream edge until I was closer to where I had heard the calls before attempting to penetrate the thick shrubbery. I could hear Graham from the darkness as he periodically paused, give his best frog call, and wait for any nearby frogs to respond so he could get a better read on their location. After any frogs answered, the branch-breaking and cursing would resume as he neared his quarry.Upon reaching what I felt was an encouraging spot; I took the plunge and began to part the branches in front of me. Despite the leaves and sticks thrashing my arms and face, I could still make out the sounds of both Sean’s imitation and the genuine article scattered throughout the wetland. At one point, after being enclosed by a wooden cell, I clicked off my headlight in exasperation and decided to just listen. When my light was off, I noticed that there were a couple frogs in the darkness surrounding me that would respond to Sean’s call from the other side of the stream. Hoping to take advantage of this revelation while simultaneously eliminating the need for me to expose myself as a second-rate frog impressionist, I kept my headlamp off and waited. Before long, a nearby frog again answered Sean. The noise was not in the muddy puddles at my feet as I might have expected, it came from the tall shrubs around me. Hindered by a log at my thigh, I strained my neck and upper body towards the sound and turned on my headlamp. Instantly, I illuminated an emerald green frog almost immediately in front of my face and perched along an eye-level branch. Pausing to confirm I was gazing at what I had previously only seen immortalized within field guides and similar mediums, I admired the brown bib in striking contrast to the bright green back of the small frog. As I watched, he inflated his vocal sac and began singing.“I’ve got one right here!”It sounded as if a bulldozer was tearing through the swamp as Sean forced himself over from the other side of the stream. I waited until he had a chance to see the frog on the branch, minding its own business, before I attempted to catch it for posed photographs at a better angle. As slimy amphibians are wont to do, however, the frog squirted out of my grasp and into the inky depths of the woody thicket. Before I was fully able to curse my bad luck, I noticed yet another frog less than a couple feet from the first. Determined not to make the same mistake again I focused on the frog’s location and slowly brought my hands around it. But as I closed in, the frog sensed danger and I saw him tense for a jump. Steeling myself for another disappointment, I watched the frog jump off its perch. As luck would have it, however, he landed straight onto my eyeball. Surprised, I slowly raised my hand to my face and gently grasped the frog. I had found and captured the elusive and rare Pine Barrens Tree Frog.All Pine Barrens Tree Frog photographs are courtesy of Aubrey Heupel, who along with Matt Greene are two skilled biologists and nature photographers (Fingerprince Prints Photography). I urge everyone to visit their website: www.fingerprinceprints.com to view their pictures. If you're looking for ideas for late birthday presents for me (and really, who isn't?) snake note cards would be exceedingly welcome.

I sure have. Every once in a while it will make the rounds through people’s inboxes. Knowing of my interest in maligned creatures, many are eager to know my thoughts on the giant snake that had been killed in the town next to theirs.

It’s odd though, how the snake has been killed in a different town each time I receive the picture and how its size, although always larger than any rattlesnake on record, fluctuates perceptibly over the years.

You likely realize what I’m getting at; this picture is one of many e-mail ruses that boast of various killer reptiles that were killed themselves just in the nick of time, often before delivering a fatal deathblow to some unwitting yet fine and upstanding citizen.

Recently upon having a casual conversation with a salesman at a local business and after revealing myself as a wildlife biologist, the man asked if I had heard about the giant diamondback rattlesnake that had just been killed in Enterprise, Alabama. Already knowing where this conversation was going, I feigned ignorance to hear the latest iteration of the Southeast’s giant dead snake. I was enthusiastically led over to a nearby counter where I saw the above picture printed out for all patrons to see. Sure enough, the attached text described how the 97 pound eastern diamondback rattlesnake had been killed in Alabama.

Diplomatically, I casually pointed out the black and white tail of the snake, reminiscent of a raccoon, and I noted how this feature reveals the snake to be a western diamondback. Although a close relative to our native eastern diamondback, the western is found no further east than Arkansas, far from Alabama, Georgia, or Florida. I continued by noting how that the snake is being held aloft toward the camera with a pair of snake tongs. For emphasis, I ran to my truck and returned with my nearly four foot long pair. I inquired how much larger a snake might appear if it was four feet closer to the camera than the man holding it. I mentioned how some fisherman may know this trick all too well.

(Side note: there’s only so much camera trickery that can be done, the fish in question should have some girth to start with for maximum effect).

Check out Mark Bailey's blog for another example and follow the links for a demonstration.

I could see that I was winning over my audience, now a few interested people crowded around the photograph, eager to hear about large rattlesnakes. One of them noted that the man in the picture didn’t seem to be struggling much for holding up a 97 pound rattlesnake. One astute individual noted dubiously, “That’s like holding two bags of fertilizer”.

I took the opportunity to talk about how although I’ve handled a number of large snakes, including four and five foot rattlesnakes, none of them surpassed ten pounds. A rattlesnake approaching one hundred pounds does not approach the realm of possibility.

As conversations of this type often do, the talk drifted to large rattlesnakes seen and killed by those present. I’ve heard of rattlesnakes reaching six feet long that are now skinned and displayed in the den, of snakes writhing on the road after being purposefully run over, et cetera, ad nauseum.

Encouragingly, sometimes this prompts some thoughtful head-nodding. On the other hand, occasionally it triggers an individual to share yet another tale of a snake being heroically vanquished and destroyed.

After hearing a couple of such stories today, one of the men noted although he’s lived in the area his entire life and come across many diamondback rattlesnakes, every last one was more interested in escaping notice or fleeing than being aggressive. Immediately, the heroic snake killing tales were put into another perspective.